<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
    /* splice(index,howmany,item)
      index-->从哪里开始
      howmany-->删除几个
      item-->在删除的地方添加值
     */
     var arr=[1,2,3,4,5];
     arr.splice(1,3,6,7);
     console.log(arr);
    </script>
</body>
</html>